Neutrophil function is preserved in a pooled granulocyte component prepared from whole blood donations

Navigating the neutropenic abyss with granulocyte transfusions: Retrospective single-center analysis of effectiveness and safety in India

BACKGROUND

Hemato-oncologic patients receiving intensive chemotherapy may develop severe neutropenia and serious bacterial and/or fungal infections. Granulocyte transfusions (GTs) may be beneficial as a bridging therapy in hemato-oncologic patients with febrile neutropenia.

AIM

To evaluate the clinical effectiveness of GTs in hemato-oncologic patients with febrile neutropenia.

MATERIALS AND METHODS

This retrospective study evaluated the effectiveness of 150 GTs in 88 hemato-oncologic patients. Donors were mobilized with granulocyte colony-stimulating factors and dexamethasone. Patients' hematological parameters (pre- and post-GT) and safety and effectiveness of GTs were analyzed.

RESULTS

The safety and effectiveness of GTs were assessed in the patients with various underlying conditions, including 78% with acute myeloid leukemia. In total, 150 GTs were administered, mostly during the chemotherapy induction phase. The GTs were well-tolerated by the patients, and a significant increment in white blood cell count and absolute neutrophil count (ANC) was noticed in 95% of patients after the transfusion. The granulocyte dose was positively correlated with ANC after the transfusion. The average time to neutrophil recovery from the last day of GT was 6.7 days, and the 30-day survival rate was 77%. The donors were all men, and a significant increase in WBC count was observed post-mobilization. The median granulocyte yield was 2.28 × 1010 /unit. All granulocyte products were crossmatched and irradiated before the transfusion.

CONCLUSION

GTs can be a useful adjunctive treatment for febrile neutropenia in hemato-oncologic patients with multidrug-resistant sepsis. However, additional studies are required for confirming their effectiveness and establishing guidelines for their use.

Clinical characteristics and risk factors of acute lymphoblastic leukemia in children with severe infection during maintenance treatment

BACKGROUND

Infection is the most common adverse event of acute lymphoblastic leukemia (ALL) treatment and is also one of the main causes of death.

METHODS

To investigate the clinical characteristics and risk factors of severe infections during the maintenance phase of ALL treatment, we conducted a retrospective study.

RESULTS

A total of 181 children were eligible and 46 patients (25.4%) suffered from 51 events of severe infection, most of which occurred in the first half year of the maintenance phase (52.9%). The most common infection was pulmonary infection (86.3%) followed by bloodstream infection (19.6%). The main symptoms of ALL patients with pulmonary infection were fever, cough, and shortness of breath. The main manifestations of computer tomography (CT) were ground glass shadow (56.8%), consolidation shadow (27.3%), and streak shadow (25%). Multivariate binary logistic regression analysis showed that agranulocytosis, agranulocytosis ≥7 days, anemia, and low globulin level were independent risk factors for severe infection during the maintenance phase (all p < 0.05).

CONCLUSIONS

Taken together, blood routine examinations and protein levels should be monitored regularly for ALL patients in the maintenance phase, especially in the first 6 months. For ALL patients with risk factors, preventive anti-infective or supportive therapies can be given as appropriate to reduce the occurrence of severe infections.

How are granulocytes for transfusion best used? The past, the present and the future

Granulocyte transfusions continue to be used in clinical practice, predominantly for treatment of refractory infection in the setting of severe neutropenia. There is biological plausibility for effectiveness in these patients with deficiencies of neutrophils, either as a consequence of disease or treatment. However, there is a chequered history of conducting and completing interventional trials to define optimal use, and many uncertainties remain regarding schedule and dose. Practice and clinical studies are severely limited by the short shelf life and viability of current products, which often restricts the timely access to granulocyte transfusions. In the future, methods are needed to optimise donor-derived granulocyte products. Options include use of manufactured neutrophils, expanded and engineered from stem cells. Further possibilities include manipulation of neutrophils to enhance their function and/or longevity. Granulocyte transfusions contain a heterogeneous mix of cells, and there is additional interest in how these transfusions may have immunomodulatory effects, including for potential uses as adjuncts for anti-cancer effects.

Granulocyte concentrate splitting does not affect phenotype and function

BACKGROUND

More granulocyte concentrates (GCs) could be produced for more patients from the same donor if apheresis bags were split and stored for longer periods of time. Hence, we tested the hypothesis that splitting and extension of storage of GCs do not impair granulocyte function or viability.

STUDY DESIGN AND METHODS

Granulocyte apheresis concentrates were produced using modified fluid gelatin as a separation enhancer, split into two portions, and stored for 24 and 48 h. Granulocyte function, represented by cell migration, reactive oxygen species (ROS) production, and neutrophil extracellular trap formation (NETosis), was measured by live-cell imaging. ROS production, adhesive surface protein expression, and viability were measured by flow cytometry.

RESULTS

Splitting had no effect on any of the tested parameters. After 24 h of storage, live-cell imaging showed no significant difference in migration, time to maximum ROS production, time to half-maximum NETosis, viability, or CD11b expression, but ROS production induced by phorbol 12-myristate 13-acetate (PMA) decreased from an initial median fluorescence intensity of 1775-590 artificial units. After 48 h, PMA-induced ROS production, viability, and migration declined, as reflected by decreases in median total distance (119 vs. 63.5 μm) and median Euclidean distance (30.75 vs. 14.3 μm).

CONCLUSION

Splitting GC products has no effect on granulocyte viability or function, but extended storage >24 h does compromise granulocyte function. The findings confirm that GCs should be transfused within 24 h of collection. Longer storage cannot be recommended.

Prolonged storage of purified granulocyte concentrates: Introduction of a new purification method

BACKGROUND

Use of donor granulocyte concentrate (GC) has been limited due to its short storage time of 6-24 h, which is partially due to residual red blood cells (RBCs) and platelets and the resulting lactate production leading to an acidotic milieu. To increase this storage time, we developed a closed system procedure compatible with standard blood bank technologies to remove RBC and platelets and to enrich the GC.

METHODS

Standard GCs (sGCs) were sedimented, washed twice with 0.9% sodium chloride (NaCl), and resuspended in blood group-identical fresh frozen plasma. The resulting purified GCs (pGCs) were then stored in platelet bags at a cell concentration of about 5 × 10⁷  ± 1.8 × 10⁷ leukocytes/ml without agitation at room temperature for up to 72 h. Cell count and viability, pH, blood gases, phagocytosis, and oxidative burst were monitored daily.

RESULTS

A significant reduction in RBC (98%) through sedimentation, and platelets (96%) by washing, purified the white blood cell (WBC) population and enriched the granulocytes to 96% of the WBC in the pGC. After 72 h of storage, over 90% of the initial WBC count of pGC remained, was viable (≥97%), and the granulocytes exhibited a high phagocytosis and oxidative burst functionality, comparable to sGC after 24 h.

CONCLUSION

Purification extends the maximum storage period of GC from 24 to 72 h and may therefore improve the availability of GC and its clinical use.

Elevated Interleukin-18 Receptor Accessory Protein Mediates Enhancement in Reactive Oxygen Species Production in Neutrophils of Systemic Lupus Erythematosus Patients

Interleukin-18 receptor accessory protein (IL18RAP) is an indispensable subunit for the IL-18 receptor (IL-18R) complex's ability to mediate high-affinity IL-18 binding and signalling transduction. Interest in IL-18 in systemic lupus erythematosus (SLE) has been mostly focused on its role as a type 1 T helper cell-driving cytokine. The functional significance of IL18RAP in mediating the IL-18-driven response in myeloid cells in SLE remains largely unexplored. This study aimed to investigate the expression and function significance of IL18RAP in neutrophils of SLE patients. By qRT-PCR and Western blot analyses, elevated expressions of IL18RAP mRNA and protein were observed in neutrophils from SLE patients-particularly those with a history of nephritis. IL18RAP expression correlated negatively with complement 3 level and positively with disease activity, with higher expression in patients exhibiting renal and immunological manifestations. The increased IL18RAP expression in SLE neutrophils could be attributed to elevated type I interferon level in sera. Functionally, neutrophils from SLE patients showed higher IL-18-mediated enhancement in reactive oxygen species (ROS) generation, which showed positive correlation with IL18RAP expression and could be neutralized by anti-IL18RAP blocking antibodies. Taken together, our findings suggest that IL-18 could contribute to SLE pathogenesis through mediation of neutrophil dysfunction via the upregulation of IL18RAP expression.

Granulocyte concentrates prepared from residual leukocyte units produced by the Reveos automated blood processing system

BACKGROUND

Granulocyte concentrates are mainly derived by apheresis technique from donors stimulated with granulocyte colony-stimulating factor and steroids. The automated blood processing system Reveos, which is now increasingly used across the world, separates whole blood into four components, including a residual leukocyte unit containing granulocytes. The aim of this study was to produce an alternative granulocyte concentrate from leukocyte units produced by the Reveos system, and to assess the function of the granulocytes.

METHODS

The number of granulocytes was measured in residual leukocyte units, derived from whole blood donations, with different volumes ranging from 10 to 40 ml. After deciding the optimal volume of the leukocyte unit (30 ml), ten ABO-matched units were pooled to form a granulocyte concentrate. The function of the granulocytes from residual leukocyte units was assessed by analyzing surface markers, phagocytosis of yeast, and production of reactive oxygen species.

RESULTS

Residual leukocyte units with a volume of 30 ml contained a median number of 0,7 × 10⁹ granulocytes, and granulocyte concentrates prepared from ten pooled 30 ml-leukocyte units contained a median number of 6,3 × 10⁹ granulocytes. Granulocytes derived from residual leukocyte units displayed surface markers associated with granulocyte function, and capability to phagocytose yeast and produce reactive oxygen species.

CONCLUSIONS

Granulocyte concentrates prepared from residual leukocyte units contain in vitro functional granulocytes and may be considered as an alternative product in acute situations before regular granulocyte concentrates from stimulated donors are available.

[Preparation of pooled granulocytes concentrates from whole blood buffy coats (PGC) as an alternative to apheresis]

BACKGROUND

The collection of granulocytes by apheresis requires volunteer donor stimulation by corticoids and the use of HES, a compound which is currently challenged by potential safety issues. Preparation of pooled granulocytes concentrates from whole blood buffy coats (PGC) represent an alternative to apheresis with a better benefit/risk for the donors.

METHOD

Whole blood is collected in a bottom and top blood bag for buffy coat preparation. After centrifugation and separation, buffy coat are obtained. Twenty ABO matched buffy coats are selected for processing into one PGC. Four pools of five buffy coats were made, platelet additive solution is added to each pool, mixed gently and centrifuged. The red cell residue, supernatant and granulocyte rich layer are separated. Two granulocyte rich layers are pooled and added with 70mL of ABO matched plasma from the initial donations (=PGC10). The final PGC (=PGC20) is obtained by pooling two PGC10 into a platelet storage bag. Neutrophil content and in-vitro functionality are assessed at day of preparation (D1) and at expiry hour, 48 hours after collection (D2).

RESULTS

On N=18, mean: Volume=408±4mL, 2.2*1010±0.24 neutrophils, Hematocrit=18%±3%, 4.7*1011platelets. Viability is well preserved: 95%±6% day of PGC preparation, 85%±7% after 24h of storage (D2). Functionality (ROS production measurement) is well preserved: 1.36±0.25 at D1 and 1.38±0.18 at D2. Expression and modulation of adhesion molecules after stimulation are normal at D1 and slightly decreased at D2 but still normal.

CONCLUSIONS

PGC20 in vitro characteristics are in conformance with the EDQM guide (V19) and similar to apheresis for granulocytes content and hematocrit. The viability and two mean indicators which explore neutrophil function are well maintained during PGC preparation and after 24 hours of storage.

The burden of invasive infections in neutropenic patients: incidence, outcomes, and use of granulocyte transfusions

BACKGROUND

Patients with prolonged neutropenia caused by chemotherapy or underlying marrow disorders are at risk of invasive bacterial and fungal infections. New treatment options alongside targeted antimicrobial therapy that might improve outcomes include granulocyte transfusions (GTX). To inform the research agenda, a prospective observational cohort study was performed in the Netherlands and United Kingdom. The aim was to describe the incidence, characteristics, and outcomes of patients developing invasive infections and assess patients fulfilling criteria for GTX.

STUDY DESIGN AND METHODS

All patients receiving myeloablative chemotherapy and anticipated to develop 7 or more days of neutropenia (<0.5 × 10⁹/L) were eligible and followed for the development of invasive infections according to a defined algorithm and mortality up to 100 days. Secondary outcomes were types of infection and eligibility for GTX.

RESULTS

A total of 471 patients enrolled at six hematology‐oncology departments were followed for 569 neutropenic episodes. Overall, 32.5% of patients developed invasive infections during their first episode. Significant baseline risk factors for developing infections were high comorbidity scores (WHO performance status ≥ 2, hazard ratio [HR], 2.6 [1.7‐3.9]; and hematopoietic cell transplantation‐comorbidity index score ≥ 2 HR 1.3 [0.9‐1.8]). Infections were bacterial (59.4%) and fungal (22.3%). Despite 34 patients (6.3% of all episodes) appearing to meet criteria to receive GTX, only nine patients received granulocytes. The HR for death was 5.8 (2.5‐13.0) for patients with invasive infections.

CONCLUSION

This study documents that invasive infections are associated with significant mortality. There is a need for new strategies to prevent and treat infections, which may include better understanding of use GTX.

See article on page 6–8, in this issue

Successful Treatment of Invasive Conidiobolus Infection During Therapy for Acute Lymphoblastic Leukemia

Invasive fungal infections are a serious cause of morbidity and mortality in patients with hematologic malignancies. Conidiobolus species are molds within the order Entomophthorales and may disseminate to become rapidly fatal in immunocompromised individuals. This species of fungal infections are often multidrug resistant (MDR) and present unique therapeutic challenges. Reports of Conidiobolus infections are rare in pediatric oncology. We report the successful treatment of an adolescent male with B-cell lymphoblastic leukemia and MDR invasive sinopulmonary Conidiobolus infection with emphasis on early and aggressive neutrophil support with surgical debridement. The strategies described could be applied to other MDR fungal infections.

An International Registry of Granulocyte Transfusions

Introduction

Granulocyte transfusions are used to either treat or prevent life-threatening infections in neutropenic patients. Current evidence from clinical trials does not support or reject efficacy, nor guide practice.

Methods

A group of investigators have led the efforts to create an online registry to gather information on granulocyte transfusion practices from as broad a range of international settings. The data forms were adapted from an on-going study in England for electronic data management. Data is collected at the time of the request for granulocytes, weekly, at 28 days, and at 6 months. Information collected includes donor, granulocyte unit, patient and illness characteristics, and outcomes.

Results

The PROspective GRanulocyte usage and outcomEs Survey (ProGrES) is currently open for data entry. Centres across the UK have collected data on 80 subjects. Five institutions from 4 countries (2 from the US, 1 each from Brazil, and national services in Canada and France) are in the process of joining the study. Other countries have expressed interest.

Conclusion

It is feasible to develop an international registry of granulocyte transfusions to characterise current practices and describe outcomes. This registry would provide a platform to explore the relationship between intervention and outcomes, and to generate evidence to inform granulocyte transfusion efficacy.

Granulocyte transfusions: A concise review for practitioners

Granulocyte transfusions (GTXs) have been used to treat and prevent infections in neutropenic patients for more than 40 years, despite persistent controversy regarding their efficacy. This narrative review attempts to complement recent systematic reviews by the Cochrane Collaboration and provide both historical context and critical assessment of the most significant clinical studies published over the years. The data suggest that properly collected and promptly infused granulocytes are active against infections, both bacterial and fungal. The most important question that remains unanswered is in which patients the administration of granulocytes will be beneficial. The preponderance of evidence suggests that granulocyte transfusions may be efficacious in few select cases as a temporizing measure to control an infection that is expected (or proven) to be refractory to optimal antimicrobial treatment, and that could otherwise be controlled by marrow recovery, which is expected to happen. In this regard, they are best considered a "bridge" that grants enough time for the recipient to develop their own response to the infection. The challenges to use GTXs successfully are both clinical, in terms of timely identifying the patients who may benefit, and logistical, in terms of optimal selection of donors and collection technique.

Granulocyte transfusions in the management of invasive fungal infections

Granulocyte transfusions have a long history of being used in patients with neutropenia or neutrophil dysfunction to prevent and treat invasive fungal infections. However, there are limited and conflicting data concerning its clinical effectiveness, considerable variations in current granulocyte transfusion practices, and uncertainties about its benefit as an adjunct to modern antifungal therapy. In this review, we provide an overview on granulocyte transfusions and summarize the evidence on their role in the prevention and treatment of invasive fungal infections.

Characterization of buffy coat-derived granulocytes for clinical use: a comparison with granulocyte colony-stimulating factor/dexamethasone-pretreated donor-derived products

BACKGROUND AND OBJECTIVES

Buffy coat-derived granulocytes have been described as an alternative to the apheresis product from donors pretreated with dexamethasone and granulocyte colony-stimulating factor (G-CSF). The latter is - dependent on the local and national settings - obtained following a demanding and time-consuming procedure, which is undesirable in critically ill septic patients. In contrast, buffy coat-derived products have a large volume and are often heavily contaminated with red cells and platelets. We developed a new pooled buffy coat-derived product with high purity and small volume, and performed a comprehensive functional characterization of these granulocytes.

MATERIALS AND METHODS

We pooled ten buffy coats following the production of platelet concentrates. Saline 0·9% was added to decrease the viscosity and the product was split into plasma, red cells and a 'super' buffy coat. Functional data of the granulocytes were compared to those obtained with granulocytes from healthy controls and G-CSF/dexamethasone-pretreated donors.

RESULTS

Buffy coat-derived granulocytes showed adhesion, chemotaxis, reactive oxygen species production, degranulation, NETosis and in vitro killing of Staphylococcus aureus, Escherichia coli and Aspergillus species comparable to control and G-CSF/dexamethasone-derived granulocytes. Candida killing was superior compared to G-CSF/dexamethasone-derived granulocytes. Immunophenotyping was normal; especially no signs of activation in the buffy coat-derived granulocytes were seen. Viability was reduced. Buffy coats are readily available in the regular blood production process and would take away the concerns around the apheresis product.

CONCLUSION

The product described appears a promising alternative for transfusion purposes.

Granulocyte transfusions in critically ill children with prolonged neutropenia: side effects and survival rates from a single-center analysis

Granulocyte transfusions for neutropenic patients have been used for over 40 years, although effectiveness, indications, and both patient and donor safety remain debated. This single-center study assessed the side effects, clinical course, and survival of granulocyte transfusions in critically ill pediatric patients, with underlying hemato-oncological disorders, prolonged neutropenia, and proven or suspected severe infection. Donor-specific side effects and influence of donor-specific characteristics on patient outcome were also investigated. A median of 4.02 × 10(10) cells was collected from 39 healthy donors for 118 granulocyte concentrates. Donors reported no significant side effects. Complications for patients were frequent but mostly minor and included vomiting, hypotension, and dyspnea. In one episode of life-threatening dyspnea, association with the granulocyte transfusion could not be ruled out. Overall survival on day 100 was 61.9 %. Patients received a median of 0.13 × 10(10) cells per kg body weight. Doses above this median were associated with a significantly better survival. Lower patient weight and age-/sex-adjusted weight were also associated with better survival.

CONCLUSION

Granulocyte mobilization and collection is a safe practice. Transfusions are well tolerated in critically ill patients. Patient weight and transfused cells per kg bodyweight are major determinants of survival in pediatric patients.

WHAT IS KNOWN

• Granulocyte transfusions for neutropenic patients have been used for over 40 years • The effectiveness of the technique remains controversial • Patient and donor safety remain debated • New mobilization protocols generate higher yields of granulocytes What is new: • Granulocyte collection can safely be performed • Granulocytes can safely be administered to patients • Lower patient weight and age-/sex-adjusted weight are associated with better survival rates • Patients receiving above 0.13 × 10 (10) cells per kg body weight had an excellent outcome • Further standardized, prospective studies are warranted.

Bacterial survival and distribution during buffy coat platelet production

BACKGROUND AND OBJECTIVES

At Canadian Blood Services, buffy coat (BC) platelet concentrates (BC-PCs) show a generally lower bacterial contamination rate than apheresis PCs. This study investigated whether the PC production method contributes to this observation.

MATERIALS AND METHODS

Whole blood (WB) inoculated with eight bacterial strains was processed using the BC method. Bacteria were enumerated throughout BC-PC production and subsequent PC storage. Endotoxin production and bacterial adhesion to PC bags were evaluated during PC storage. PC quality was monitored by CD62P expression (flow cytometry) and changes in dynamic light scattering (ThromboLUX^® ).

RESULTS

During overnight WB hold, Staphylococcus epidermidis titres remained unchanged, commercial Escherichia coli and Klebsiella pneumoniae were eliminated and the remaining organisms proliferated to high concentrations. Through BC-PC production, bacteria segregated preferentially towards the cellular fractions compared to plasma (P < 0·05). During PC storage, most bacteria adhered to the PC bags and Gram negatives produced clinically significant endotoxin levels. Changes in CD62P expression or ThromboLUX scoring did not consistently reflect bacterial contamination in BC-PCs.

CONCLUSION

WB hold during BC-PC production does not have a broad-spectrum bactericidal effect, and therefore, other factors contribute to low rates of contamination in BC-PCs.

Granulocyte transfusions for treating infections in people with neutropenia or neutrophil dysfunction

BACKGROUND

Despite modern antimicrobials and supportive therapy bacterial and fungal infections are still major complications in people with prolonged disease-related or treatment-related neutropenia. Transfusions of granulocytes have a long history of usage in clinical practice to support and treat severe infection in high-risk groups of patients with neutropenia or neutrophil dysfunction. However, there is considerable current variability in therapeutic granulocyte transfusion practice, and uncertainty about the beneficial effect of transfusions given as an adjunct to antibiotics on mortality. This is an update of a Cochrane review first published in 2005.

OBJECTIVES

To determine the effectiveness and safety of granulocyte transfusions compared to no granulocyte transfusions as adjuncts to antimicrobials for treating infections in people with neutropenia or disorders of neutrophil function aimed at reducing mortality and other adverse outcomes related to infection.

SEARCH METHODS

We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 2). MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1937), the Transfusion Evidence Library (from 1980) and ongoing trial databases to 11 February 2016.

SELECTION CRITERIA

RCTs comparing people with neutropenia or disorders of neutrophil dysfunction receiving granulocyte transfusions to treat infection with a control group receiving no granulocyte transfusions. Neonates are the subject of another Cochrane review and were excluded from this review. There was no restriction by outcomes examined, language or publication status.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by the Cochrane Collaboration.

MAIN RESULTS

We identified 10 trials that met the inclusion criteria with a total of 587 participants. We also identified another ongoing trial. These trials were conducted between 1975 and 2015. None of the studies included people with neutrophil dysfunction. The studies differed in the type of infections they included. Six studies included both children and adults, however data were not reported separately for children and adults. The two newest studies gave granulocyte colony stimulating factor (G-CSF) to donors; both were stopped early due to lack of recruitment. Three studies re-randomised participants and therefore quantitative analysis was unable to be performed.Overall the quality of the evidence was very low to low across different outcomes according to GRADE methodology. This was due to many of the studies being at high risk of bias, and many of the outcomes being imprecise.There may be no difference in all-cause mortality over 30 days between participants receiving therapeutic granulocyte transfusions and those that did not (six studies; 321 participants; RR 0.75, 95% CI 0.54 to 1.04; very low-quality evidence). There were no differences between the granulocyte dose subgroups (< 1 x 10(10) per day versus ≥ 1 x 10(10) per day) (test for subgroup differences P = 0.39). There was a difference in all-cause mortality between the studies based on the age of the study (published before 2000 versus published 2000 or later) (test for subgroup differences P = 0.03). There was no difference in all-cause mortality between participants receiving granulocyte transfusions and those that did not in the newest study (one study; 111 participants; RR 1.10, 95% CI 0.70 to 1.73, low-quality evidence). There may be a reduction in all-cause mortality in participants receiving granulocyte transfusions compared to those that did not in studies published before the year 2000 (five studies; 210 participants; RR 0.53, 95% CI 0.33 to 0.85; low-quality evidence).There may be no difference in clinical reversal of concurrent infection between participants receiving therapeutic granulocyte transfusions and those that did not (five studies; 286 participants; RR 0.98, 95% CI 0.81 to 1.19; low-quality evidence).There is insufficient evidence to determine whether there is a difference in pulmonary serious adverse events (1 study; 24 participants; RR 0.85, 95% CI 0.38 to 1.88; very low-quality evidence).None of the studies reported number of days on therapeutic antibiotics, number of adverse events requiring discontinuation of treatment, or quality of life.Six studies reported their funding sources and all were funded by governments or charities.

AUTHORS' CONCLUSIONS

In people who are neutropenic due to myelosuppressive chemotherapy or a haematopoietic stem cell transplant, there is insufficient evidence to determine whether granulocyte transfusions affect all-cause mortality. To be able to detect a decrease in all-cause mortality from 35% to 30% would require a study containing at least 2748 participants (80% power, 5% significance). There is low-grade evidence that therapeutic granulocyte transfusions may not increase the number of participants with clinical resolution of an infection.

Granulocyte transfusions for preventing infections in people with neutropenia or neutrophil dysfunction

BACKGROUND

Despite modern antimicrobials and supportive therapy, bacterial and fungal infections are still major complications in people with prolonged disease-related or therapy-related neutropenia. Since the late 1990s there has been increasing demand for donated granulocyte transfusions to treat or prevent severe infections in people who lack their own functional granulocytes. This is an update of a Cochrane review first published in 2009.

OBJECTIVES

To determine the effectiveness and safety of prophylactic granulocyte transfusions compared with a control population not receiving this intervention for preventing all-cause mortality, mortality due to infection, and evidence of infection due to infection or due to any other cause in people with neutropenia or disorders of neutrophil function.

SEARCH METHODS

We searched for randomised controlled trials (RCTs) and quasi-RCTs in the Cochrane Central Register of Controlled Trials (Cochrane Library 2015, Issue 3), MEDLINE (from 1946), EMBASE (from 1974), CINAHL (from 1937), theTransfusion Evidence Library (from 1980) and ongoing trial databases to April 20 2015.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs comparing people receiving granulocyte transfusions to prevent the development of infection with a control group receiving no granulocyte transfusions. Neonates are the subject of another Cochrane review and were excluded from this review. There was no restriction by outcomes examined, but this review focuses on mortality, mortality due to infection and adverse events.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS

Twelve trials met the inclusion criteria. One trial is still ongoing, leaving a total of 11 trials eligible involving 653 participants. These trials were conducted between 1978 and 2006 and enrolled participants from fairly comparable patient populations. None of the studies included people with neutrophil dysfunction. Ten studies included only adults, and two studies included children and adults. Ten of these studies contained separate data for each arm and were able to be critically appraised. One study re-randomised people and therefore quantitative analysis was unable to be performed.Overall, the quality of the evidence was very low to low across different outcomes according to GRADE methodology. This was due to many of the studies being at high risk of bias, and many of the outcome estimates being imprecise.All-cause mortality was reported for nine studies (609 participants). There was no difference in all-cause mortality over 30 days between people receiving prophylactic granulocyte transfusions and those that did not (seven studies; 437 participants; RR 0.92, 95% CI 0.63 to 1.36, very low-quality evidence).Mortality due to infection was reported for seven studies (398 participants). There was no difference in mortality due to infection over 30 days between people receiving prophylactic granulocyte transfusions and those that did not (six studies; 286 participants; RR 0.69, 95% CI 0.33 to 1.44, very low-quality evidence).The number of people with localised or systemic bacterial or fungal infections was reported for nine studies (609 participants). There were differences between the granulocyte dose subgroups (test for subgroup differences P = 0.01). There was no difference in the number of people with infections over 30 days between people receiving prophylactic granulocyte transfusions and those that did not in the low-dose granulocyte group (< 1.0 x 10(10) granulocytes per day) (four studies, 204 participants; RR 0.84, 95% CI 0.58 to 1.20; very low-quality evidence). There was a decreased number of people with infections over 30 days in the people receiving prophylactic granulocyte transfusions in the intermediate-dose granulocyte group (1.0 x 10(10) to 4.0 x 10(10) granulocytes per day) (4 studies; 293 participants; RR 0.40, 95% CI 0.26 to 0.63, low-quality evidence).There was a decreased number of participants with bacteraemia and fungaemia in the participants receiving prophylactic granulocyte transfusions (nine studies; 609 participants; RR 0.45, 95% CI 0.30 to 0.65, low-quality evidence).There was no difference in the number of participants with localised bacterial or fungal infection in the participants receiving prophylactic granulocyte transfusions (six studies; 296 participants; RR 0.75, 95% CI 0.50 to 1.14; very low-quality evidence).Serious adverse events were only reported for participants receiving granulocyte transfusions and donors of granulocyte transfusions.

AUTHORS' CONCLUSIONS

In people who are neutropenic due to myelosuppressive chemotherapy or a haematopoietic stem cell transplant, there is low-grade evidence that prophylactic granulocyte transfusions decrease the risk of bacteraemia or fungaemia. There is low-grade evidence that the effect of prophylactic granulocyte transfusions may be dose-dependent, a dose of at least 10 x 10(10) per day being more effective at decreasing the risk of infection. There is insufficient evidence to determine any difference in mortality rates due to infection, all-cause mortality, or serious adverse events.

Granulocyte Transfusion Therapy

Bacterial and fungal infections continue to be a major cause of morbidity and mortality in severely neutropenic patients undergoing aggressive chemotherapy regimens or hematopoietic stem cell transplantation. Traditional granulocyte transfusion therapy, a logical approach in treating these infections, has been available for many years, and several controlled studies have shown this therapy to be useful. However, granulocyte transfusion therapy fell out of favor because the results were not clinically impressive, and adverse results were reported. These disappointing results were felt to be, in part, because of the low doses of granulocytes provided. More recent studies have attempted to increase the numbers of transfused cells by stimulating normal granulocyte donors with G-CSF (+/-corticosteroids). With these techniques, the number of granulocytes transfused can be increased 3-4 fold. The cells have been shown to circulate in recipients, and daily transfusions are capable of maintaining normal or near-normal blood neutrophil counts in previously severely neutropenic patients. The cells appear to function normally by a variety of in vitro and in vivo tests. Clinical benefit, as defined by survival or clearance of infection, has not been definitively determined. Results of an ongoing randomized controlled clinical trial should be available in the near future.

The granulocytes in neutropenia 1 (GIN 1) study: a safety study of granulocytes collected from whole blood and stored in additive solution and plasma

OBJECTIVE/AIM

To evaluate the safety of transfusing pooled, whole blood-derived granulocytes in additive solution and plasma (GASP) in 30 recipients.

BACKGROUND

Demand for granulocytes in England has increased five-fold. With the advantages of reduced red cell, plasma and overall volume, GASP maintains function in vitro.

METHODS AND MATERIALS

Observations were recorded prior to and post transfusion. Increments were recorded at 1 h and the following morning. Leucocyte antibody screening was undertaken prior to and at 1-6 months following transfusion.

RESULTS

Thirty patients aged between 8 months and 68 years received 221 GASP in 148 transfusion episodes. GASP contained an average of 1.0 × 10(10) granulocytes in 207 mL. Adults usually received two packs and children 10-20 mL kg(-1). Children and adults received a median [interquartile range (IQR)] dose of 12.5 (9.1-25.3) and 19.7 (12.0-25.8) × 10(9) granulocytes per transfusion, respectively. There was one episode of transfusion-associated circulatory overload (TACO) in a patient with chronic cardiac failure following 600 mL of unpooled granulocytes, other fluids and one GASP. New leucocyte alloimmunisation occurred in 3/30 recipients 10%. No other significant reactions were reported. Median peripheral blood neutrophil increments at 1 h post transfusion were 0.06 (IQR, 0.01-0.17) in children and (0.03) (IQR, 0-0.16) in adults.

CONCLUSION

GASP has a similar safety profile to other sources of granulocytes for patients with refractory infection or in need of secondary prophylactic transfusion. Further studies are required to clarify the role of GASP in the treatment of neutropenic patients.

Maintenance of surface antigens and the absence of an apoptotic marker are observed during storage of granulocyte concentrates collected by bag separation method

Granulocytes were collected by the bag separation method and stored in whole blood for up to 72h. We evaluated the expressions of various surface antigens: CD62L, CD11b, CD18, CD64, CD16b, and CD95. Apoptosis was assessed both by flow cytometry and by light microscopy. Expression levels of all the surface antigens were shown to be maintained during storage for up to 72h. Approximately 80% of granulocytes were annexin V negative until 72h after collection. The storage of granulocyte concentrates collected by the bag separation method may maintain granulocyte surface antigens and lack an apoptotic marker.

Polycythemia in an infant secondary to granulocyte transfusions

Granulocyte transfusions may be useful for neutropenic pediatric patients with refractory bacterial or fungal infections. Many potential adverse sequelae associated with granulocyte transfusions are well recognized, including febrile reactions, fluid overload, alloimmunization, and lung injury. Other potential adverse sequelae, however, are less well known. This case report describes an infant with familial hemophagocytic lymphohistiocytosis who developed polycythemia (hemoglobin 10-17.6 g/dl) following four daily transfusions of 20 ml/kg of apheresis collected, steroid stimulated donor granulocytes. Expanded knowledge of potential risks of transfused granulocytes will allow for rapid recognition of transfusion-related complications, should they occur.

Granulocyte transfusions for preventing infections in patients with neutropenia or neutrophil dysfunction

BACKGROUND

Since the late 1990s there has been increasing demand for donated granulocyte transfusions to treat or prevent severe infections in patients who lack their own functional granulocytes. Other than in neonates, no systematic reviews have been performed for over 10 years relating to the efficacy of prophylactic granulocyte transfusions.

OBJECTIVES

To determine the effectiveness and safety of granulocyte transfusions compared with a control population not receiving this intervention for preventing mortality due to infection or due to any other cause in patients with neutropenia or disorders of neutrophil function.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) Issue 3, 2008, MEDLINE, EMBASE and other specialised databases up to October 2008. We also searched reference lists of articles and contacted experts in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing patients receiving granulocyte transfusions to prevent the development of infection with a control group receiving no granulocyte transfusions. Neonates have been the subject of a recent review and were excluded. There was no restriction by outcomes examined, but this review focuses on mortality, mortality due to infection and adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed potentially relevant studies for inclusion. Data were extracted by two review authors and the methodological quality was examined. Data were analysed using random and fixed effects models.

MAIN RESULTS

Ten trials met the inclusion criteria. Allocation in all trials was random, with the control arm receiving no prophylactic therapy, except one trial in which the control group received specific prophylactic antibiotics. One study reported biological randomisation based upon the availability of suitably matched, related donors rather than strict randomisation. All trials were conducted over twenty years ago with one exception, a study from 2006 in which donors were pre-medicated with granulocyte colony stimulating factor (G-CSF) resulting in significantly higher mean doses of granulocytes collected for transfusion. Different policies otherwise applied for the schedule for transfusion, method of granulocyte procurement and criteria for defining infection. Combining the results showed a relative risk (RR) for mortality of 0.94 (95% confidence intervals (CI) 0.71 to 1.25). Exclusion of the two trials which reported transfusion of an average number of granulocytes below 1 x 10(10) indicated a summary RR for mortality and mortality due to infection of 0.89 (CI 0.64 to 1.24) and 0.36 (0.14 to 0.96) respectively.

IMPLICATIONS FOR CLINICAL PRACTICE

The controlled trials that have been identified raise the possibility that prophylactic granulocyte transfusions at a dose of at least 1 x 10(10) may reduce the risk of mortality from infection. Overall mortality was not affected. However, the majority of studies were performed decades ago, and standards of supportive care have advanced considerably. These earlier trials were also based on transfusing lower yields of collected granulocytes than currently recommended. It is difficult to recommend prophylactic granulocyte transfusions outside the setting of ongoing controlled trials, given the resource and cost implications.

IMPLICATIONS FOR RESEARCH

Larger trials are needed to establish the validity of the potential benefits raised by this review, in view of the methodological limitations, the small sample sizes and the heterogeneous definitions of infection that were encountered in the included studies.